nightgown vs négligée

nightgown

noun
  • A long loose robe worn mainly by women for sleeping in. 

  • A dressing gown. 

négligée

noun
  • A woman's loose-fitting nightgown, especially when short, lacy and/or revealing; a nightie. 

  • A necklace of beads, pearls etc. 

adj
  • In the style of a negligee; revealing, titillating. 

How often have the words nightgown and négligée occurred in a corpus of books? (source: Google Ngram Viewer )